Apparatus for making terne sheets or plates



Jan. 26,1943. D, TfHADDOC'K 2,309,585

APPARATUS FOR MAKING TERNE SHEETS OR PLATES Filed Feb. l2, 1941 [Qweizla: .0n/WEL 7. Hna/206K,

Patented Jan. 26, 1943 APPARATUS Fon MAKING TERNI.:

, SHEETS R rLA'rEs Daniel T. Haddock, Tucson, Ariz. Application February 12, 1941, Serial No. 378,644

4 Claims. (Cl, S31-12.7)

This invention relates to terne sheets or plates and, more particularly, to such apparatus as is employed therein.

'Heretofore in making terne (lead-tin) sheets or plates, itl was notfpossible to secure the desired amount of coating on the first pass of the sheet through the molten bath, whlchnecessitated rerunning the material several times therethrough until the desired weight of coating was attained. 'Ihe weight of terne practically runs between 8 and 40 pounds, which figures express the weightv of coating necessary to coat 112 sheets' or plates,

each by 28" in size, or the equivalentthereof.

It is among the primary objects of this invention to deposit the-exact amount of terne coating desired 4on a metallic sheet or plate by yonly one passage thereof through the molten bath.

To the accomplishment of these and other desirable objects and purposes, I have designed the present, preferred embodimentsof the invention presented in the accompanying drawing forming a part of this specification and to which reference should be had in connectionl with the vfollowing detailed description, and in the drawing, for simplicity, like reference numerals have be rerun through 'the pot one or more times in order to bring the thickness or weight of the coating up to the desiredextent. Thus, in obtaining 9.40 pound coating, as previously described, it was necessaryto rerun a terne coated vsheet at least twice through the molten bath.

Inthe art of coating` with molten metals, most frequently the coating 'rolls are smooth. In terne coating it has been proposed to provide exit rolls-corresponding to the rolls 8, described hereinbefore. which embody helical grooves, the helix of the groove of one roll opposing the helix of the groove of the opposing roll. At certain sustained speeds these rolls, embodying single helicalgrooves, function in such manner that there is deposited on the sheet or plate a terne coating'of the desired weight. 'I'his constitutes an been employed .to designate the `same parts throughout the several views. v

Figurel is a sectionalviewof a typical terne P012;

. Figure 2 is an enlargedelevation of one `of therrolls'of the terne coating pot of Figure 1:

lFigure 3 is anenlarged fragmentary area of the roll of Figure2; and l Figure 4 is anrenlarged cross-section of a portion of the roll of Figure 2 showing the'depth and spacing of grooves on its outer surface which is used for 40 pound coatings.

Referringl more particularly to the drawing,

the numeral 2 designates a typical coating pot in Vwhich is retained molten terne (lead-tin) 3. As

indicated by the arrows, the sheet to be coated is fed in any manner desired, through'the flux box 4 at the entrance end of the pot and between guides 5 toward the exit end. during which it is coated on both sides with terne. The coated sheet is then fed through an oil box 6 and al; the

' same time passes between a pair of driven rolls 8 which smooth the semi-molten coating, after which it emerges therefrom and is cooled by the atmosphere.

I'he present invention comprises material changes in the surface of either or both of these rolls 8. Heretofore, sheets coated with ternel always ran light to weight of coating and if, as

usual, a heavy coating was desired, they had to improvement over the smooth-faced rolls, the use of which necessitated rerunning. At somewhat increased speeds made necessaryby change in consistency of the molten terne, the rolls havying,single helical grooves exert awipingl action l which is deleterious to the obtaining of a coating of the required weight. f

According to the teachingsof the present invention,v there is provided on the face of either or both of the rolls. l opposed helical grooves which are identical in `shape and pitch with the yresult that the surface of the said roll comprises even, diamond-shaped patterns and correspondingly even, separating grooves, the surfaces of the said patterns being substantially cylindrical. It has been discovered that these opposed hehcal grooves on asingle roll should be no deeper than 0.01"-, spaced approximately W' apart and substantially V-shaped, with the walls extending at substantially degrees.

These opposed' helical grooves may be formed by taking a spiral cut in onev direction from one end of the roll to the other, reversing the direction of out, and cutting identical grooves in the opposite direction, thereby producing on the surfaceof the roll a-uniformly distributed matte of diamond-shaped projections as aforesaid. Thus,

for example, for a roll of 4%" diameter, each of the opposed helices would take a 31/2" lead. 'I'he weight of coating obtained is more or less proportional to the size or the area of the opposed helical grooves, the larger the groove the` greater the weight of coating and vice versa. In no case, however, should the groove exceed a depth of 0.01". It has been discovered that for obtaining a 20 pound terne coating, a depth of 0.004" is satisfactoryu Accordingly, for various weights of coating it is only necessary to vary the area of the diamond-shaped patterns, which is best accomplished by varying the depth of the grooves. It will be apparent, however, that the size of the area can also be changed by varying the space or pitch and shape of the groove.

When using rolls of approximately 41/2" with the opposed helical grooves given a 31/2" lead with 5/8" between the bottoms thereof, and the grooves being substantially V-shaped with the sides thereof extending at substantially 60 degrees and of a depth of approximately 0.004", smooth and even 20 pound terne coatings may be obtained; and if the speed of the rolls is increased, necessitated by a change in the consistency of the molten terne, the coating will not vary therewith.

The 31/2 lead given the opposed helical groove in a roll of 45/2" diameter constitutes an angle of approximately 'l5 degrees, as shown in the developed surface of Figure 5 of the drawing. In a direction circumferentially of the roll the patterns are elongated, as distinguished fromsquare.

'The increase in theangularity referred to hereinbefoxe from `75 degrees toward 90 degrees will result in further elongation in the direction stated, while a decrease in the angularity of 75 degrees will `increase tendency toward a square; I have found, however, that the angle of 75 degrees. while susceptible of some variation in either direction, is ideal for the purpose stated.

While I have shown and described certain speciiic embodiments of the present invention, it will be understood that I do not wish to be llmited exactly thereto, since various modifications may be made without departing from-the scope of the invention as denned by the following claims.

This application is in part a continuation of an application Ser. No. 121,652 iiled Jan. 21, 1937.

I claim: i

1. In ak machine for teme-coating sheets or plates, a pair of opposed rotary exit rolls, at least one of said rolls being only partially immersed in theoil bath of said machineand having opposed helical grooves, each of said opposed vhelical 2. In a machine for terne-coating sheets or plates, a pair of opposed rotary exit rolls, at least one of said rolls being only partially immersed in the oil bath of said machine and having opposed helical grooves, each of said opposed helical grooves being V-shaped and having a depth of no greater than 0.01", said grooves being substantially identical in shape and pitch to thereby provide even diamond-shaped patterns, the greatest dimensions o! said diamond-shaped patterns being peripherally oi' the roll embodying the same. the distance between the bottoms of parallel grooves beingV approximately Vs", the surfaces of said diamond-shaped patterns being substantiall ly cylindrical whereby heavyvand even coatings may be secured in a single passage of the sheet or plate through the machine.

3,'In a machine for teme-coating sheets or plates, a pair of opposed rotary exit rolls, at'

least one ofsaid rolls being only partially immersed in the oil bath oi said machine and having opposed helical grooves, each of said opposed helical grooves being V-shaped and having a depth ofno greater than 0.01", said grooves being substantially identical in shape and pitch to thereby provide even diamond-shaped patterns,

the greatest dimensions of said diamond-shaped patterns being peripherally of the roll embodying the same, the pitches of said grooves deiining approximate '75a angles with respect to the roll axis,

the surfaces of said diamond-shaped patterns being substantially cylindrical whereby heavyand even vcoatings may be secured in a single passage of the sheet or plate through the machine.

4. In a machine for terne-coating sheets or plates, a pair of opposed rotary exit rolls, at least one of said rolls being only partially immersed in the oil bath of said machine and having opposed helical grooves, each of said opposed helical grooves beingv-shaped and having a depth of no greater than 0.01", said grooves being substantially identical in shape and pitch to thereby provide even diamond-shaped patterns, the greatest dimensions of saidfdiamond-shaped patterns being peripherally oi the roll embodying the same, the distance between the botoms of parallel grooves being approximately l/sf', the pitches of said grooves defining approximate angles with respect to the rollaxis, the surfaces of said diamond-shaped" patterns being substantially cylindrical whereby heavy and even coatings may be secured in a single passage' of the sheet or plate through the machine.

DANIEL T. 

